How smooth should the throttle be?

Howdy,

I finally got a running bike in my hands. This is the first time I ride a bike and I was practicing on the driveway to let the clutch go.

The bike idles just a tad under 1k rpm, when I let the clutch go slowly the bike will start rolling but it seems like if I don't give it a little gas it will stall. After a few rolls forward of I went on the street, noticed that it didn't feel like giving gas to a car, it was a bit jerky I was being really careful with the throttle and it seems like something catches and it wants to take off.

Not sure if it is the carbs or the throttle cable... since this is the very first time I was on a bike I have no point of reference.

It was exciting but I was a tad nervous about bake on hand, foot, clutch on one foot, brake on other hand... it was almost like learning my RC planes all over again but now I am on top of the thing.

 

sounds like you have a low idle (to me anyways) if you change the position of the choke does that help at all? i know sometimes i forget about the choke cable after the bike gets warmed up and i try to move and it just dies and i lok like a fool infront of my friends, lol try adjusting your idle screw a bit i think the idle should be closer to 1200.

 

The "Mechanical" operation should be silky-smooth.

Twisting the Grip and causing the Cable to be pulled should not be hindered. The only resistance should be the return spring.

If what you are experiencing is a noticeable "Hesitation" upon opening the Throttles, ... you are likely Tuned ::: too Lean :::

If you suspect that you are to Lean ...
CHECK your Spark Plugs.

If your Spark Plugs look to be Clean, White and devoid of Coloration, ...
You have a MIXTURE Problem that needs to be corrected.

 

Your clutch and throttle operation go hand in hand. Its called the "Friction Zone"
The right amount of clutch, coupled with the right amount of throttle, will make for smooth riding.
If everything is mechanically sound, its just you. You gotta practice, and get the feel for your friction zone. Youll learn alot when you start shifting from 1st to 2nd, so on a so forth, and even downshifting.
Thats called Rev Matching.
Youll get her. Practice Young Panda

 

Did anyone consider that the cables may need lubrication. I'm a newbie but my cables were dry when I brought my XJ. Oiling the cables on my bike went a long way and may remove some of that throttle jerkiness / tightness you are experiencing

 

Thank you all for the pointers, I will start by lubricating the throttle cable and adjusting the idle to get it up to 1,200 rpm.

It does feel like it fires better when it is idled with the choke cable not all the way to the off position so I will try that.

I will also check the spark plugs, does anybody know what the "normal" temperature for exhaust pipes should be? I can get IR thermometer and check them.

 

I believe the idle should be set to....1050 rpm....that is the setting for an XJ750J.......maybe it is 1200 rpm for a 650.....

Make sure your throttle linkage is not binding anywhere......

Have fun learning on your new bike.....

 

No, only the 550 should idle as high as 1200. If this is the 650, specs say idle should be 1050 +/- 50-same for 750? Is this your hybrid bike?

I don't think you have any mechanical issues based on your description. What the Kid told you about the f-zone is accurate. Bikes aren't like cars especially in 1st gear and they take some getting used to. Like anything else you need time and practice and soon you will get very smooth with the whole process. I still remember learning to ride at age 6 on a 80cc dirt bike and learning that initial combo of throttle and clutch was the hardest part by far!!

What will help you is to let the bike get warm first before you try and drive off. On a warm day (like now) it should be about 2 minutes or so of running and you should have a steady idle w/o the enrichment needed. Then if possible let the bike roll a bit as you ease the clutch 'out' and ease the throttle 'on' at the same time, as the clutch begins to catch you don't need any more throttle, just let the bike accelerate gradually and once rolling well and winding up, go for 2nd and your off!!

As far as exhaust temp: it depends on where on the pipes your measuring, the engine in question, the ambient temp, how warm the mill is, how hard you've been riding, etc. So it varies a LOT! When you shut down at the hottest point (so hard riding on a hot day) you shouldn't hear pronounced, rapid exhaust 'pinging.' If the 'pings' are coming faster than one per second, pipes are bluing, oil is getting dark quickly after a change, or idle is self-adjusting down; then your getting too hot.

 

with my 750 after I let it warm up (2 to 5 min) I leave the choke on the slightest bit when I take off because I noticed my bike also idles below 1000rpm ONLY when cold with no choke. once I get a couple km's from my house I turn the choke off the rest of the way and it idles up just over 1000rpm as it should.

old vehicles are like dogs... its not the dog getting trained, its the owner.
you just have to learn how your bike likes to be treated and get used to it.

 

I have done a little trouble shooting, it seems like after starting if i leave the choke for 2 minutes for it to warm up it settles better and right at 1,000 rpm.

I checked the spark plugs and found 2 things:

A) one of the cables boot is broken, the very bottom rubber came off the cable.
B) all spark plugs showed a bit of black on the inside (a bit of carbon) buildup, i don't know how old they are but may just get new ones and go from there.

Once the engine was warm and the choke was off the engine settled at 1,000 rpm, I notice the trottle hanging but realized that the cruise contol contraption was dragging on the throttle. Once i got that loose i slowly rev'ed up the engine. It responds smoothly up until 2k rpm from there and without moving the throttle any further it shoots to 5k rpm where it holds steady. If I gave it more gas it will go up steadily, if I let it go it will drop just below 2k.

When i lowered the side stand the safety kicked in and shut the engine off. I tried to restart but nothing happened. I noticed that not even the neutral light was coming on when shifting to neutral. I turned everything off, checked the fuse box and found the original box, no fuses blown nor any warmth on them.
I turned the switch on and the neutral light came on and restarted right away.

So I will get new spark plugs and try to repair the rubber boot on the spark plug.

Any suggestions or other tests that may help troubleshoot it would be welcome. I may also give it an oil change just to eliminate as many variables as possible.